package com.example.gulimall.cart.interceptor;

import com.example.gulimall.cart.vo.UserInfoTo;
import com.warren.common.constant.AuthServerConstant;
import com.warren.common.constant.CartConstant;
import com.warren.common.vo.MemberRespVo;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;

/**
 * 在执行目标方法之前，判断用户的登录状态。并封装传递给controller目标请求
 */
public class CartInterceptor implements HandlerInterceptor {

    public static ThreadLocal<UserInfoTo> threadLocal = new ThreadLocal<>();

    //在业务执行之后
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        UserInfoTo userInfoTo = new UserInfoTo();
        HttpSession session = request.getSession();
        MemberRespVo memberRespVo = (MemberRespVo)session.getAttribute(AuthServerConstant.LOGIN_USER);

        if (memberRespVo != null){
            //进入if表示用户当前已经登录
            userInfoTo.setUserId(memberRespVo.getId());
        }

        Cookie[] cookies = request.getCookies();
        if (cookies != null && cookies.length > 0){
            for (Cookie cookie : cookies){
                //user-key
                String name = cookie.getName();
                if (name.equals(CartConstant.TEMP_USER_COOKIE_NAME)){
                    userInfoTo.setUserKey(cookie.getValue());
                    userInfoTo.setTempUser(true);
                }
            }
        }
        //如果没有临时用户，一定分配一个临时用户
        if (StringUtils.isEmpty(userInfoTo.getUserKey())){
            String uuid = UUID.randomUUID().toString();
            userInfoTo.setUserKey(uuid);
        }

        //目标方法执行之前
        threadLocal.set(userInfoTo);
        return  HandlerInterceptor.super.preHandle(request,response,handler);
    }

    //在业务执行之前
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        UserInfoTo userInfoTo = threadLocal.get();

        //如果没有临时用户，一定保存一个临时用户
        if(!userInfoTo.isTempUser()){
            Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME, userInfoTo.getUserKey());
            cookie.setDomain("gulimall.com");
            cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
            response.addCookie(cookie);
        }
        HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);
    }
}
